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2012 Kawasaki KX450F Comparison

Wednesday, January 4, 2012

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2012 Kawasaki KX450F - Motocross Shootout Video
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Kawasaki’s KX450F goes head-to-head against the world’s best 450-class motocross bikes. Find out how it does in the 2012 Kawasaki KX450F Comparison Video
Team Green enters this year’s contest with its heavily updated 2012 Kawasaki KX450F ($8399). Kawasaki has always been known for the borderline psychotic power of its engine but recently it’s come up short in terms of having the total package, that is, until now.

Despite not offering electric start, the big KX’s engine is so willing to fire with even a lazy kick that it almost doesn’t even need e-start. Dial-in a handful of throttle and it’s clear that the green machine has extra juice under the hood. Power comes on strong even at low revs and if you’re not ready for it (holding on tight), the KX mill can feel a bit overwhelming.
“The power is just insane,” remarks Simon. “It hits hard on the bottom, the mid-to-top – just everywhere the power is awesome. But I think for a beginner/novice rider who is just riding for fun on the weekends — it might be a little bit much because it’s hard bike to hang onto for a long-time because it’s a race bike.”

“The engine is out of control fast,” concurs Garcia. “It’s almost like a built outdoor bike from the factory. But the power still comes on smooth — it’s definitely snappy pretty much everywhere, but still manages to be smooth.”

The Kawasaki offers adequate handling but the engine is what really shines on it.
With so much power available the rear tire has a propensity to spin off corners.
Each one of our testers picked the Kawasaki as the bike they would want to go racing with.
(Top) The Kawasaki offers adequate handling but the engine is what really shines on it. (Center) With so much power available the rear tire has a propensity to spin off corners. (Below) Each one of our testers picked the Kawasaki as the bike they would want to go racing with.
When strapped on our dyno the KX engine blew us away with how much power it pumps out. Although torque comes on a little slower than the other bikes initially, it soon surpasses the competition en route to its maximum figure of 29.28 lb-ft at 7200 rpm (highest figure). The Kawi produces class-leading horsepower too with 45.88 available at 9000 rpm. That’s over two more ponies than the next most powerful machine (RM-Z450). Looking at the power graphs demonstrates that the KX mill stomps everything in its path through the mid-range. Despite making all that power the Kawi has relatively quiet muffler that reduces the exhaust noise levels to 93.6 dB, though, it certainly sounded like it had a more aggressive pitch from behind the handlebar.

The Kawasaki has always been a class porker and this one is no exception. It weighed in at 241 pounds without any fuel in its 1.64-gallon tank, tying the Yamaha for fourth place in that category. For reference that is nine pounds heavier than the featherweight Honda but only four more pounds than the displacement handicapped 350 SX-F.

In the holeshot acceleration test the Kawasaki zoomed across the 175 foot start straightaway almost acing the Honda for the top spot coming in 0.04 seconds behind it. (Ed. Note: We did the holeshot test manually without the use of the electronic holeshot device as when conditions are optimum it produces faster acceleration times). Considering its monster engine performance we were surprised when the Kawi posted up its 2.87 second roll-on time (sixth-place), which may be attributed to excessive wheelspin since it puts such a heavy load on the back tire. For the most part our testers got along with the green bike’s drivetrain and didn’t really complain about anything. Gearing felt a little wide but since the engine has so much power everywhere it made seem not so noticeable.

Out on track the KX held its own in the handling department. Sure it doesn’t turn with the same-level of agility as the Suzuki or Honda, or even 350 KTM, it does however steer predictability and holds a line well. It’s also pretty stable considering how much power it has.

But not all of our testers agreed, as See notes: “It was a little hard for me to maneuver in the tight corners. The bike feels really tall and long. It’s also not the lightest feeling bike either.”

The green bike made up for its mid-pack handling score in the ergonomics department, with the Kawi receiving near universal praise for its cockpit and industry-leading control adjustability. It’s leaner through the mid-section and slimmer radiator shrouds allow riders to shift weight up front to aid turning.

The Kawasaki KX450F feels like it has the power to hurl you off of any obstacle.
The Kawasaki still feels a little larger than the other bikes.
The Kawasaki KX450F has one of the best engines weve ever ridden with.
(Top) The Kawasaki KX450F feels like it has the power to hurl you off of any obstacle. (Center) The Kawasaki still feels a little larger than the other bikes. (Bottom) The Kawasaki KX450F has one of the best engines we’ve ever ridden.
“I really like the riding position,” comments Taylor. “It is very similar to the Suzuki so it really fits me well. It’s a pretty good all-around bike. It’ll fit a novice guy just as well as any top pro because it’s so easy to control and it’s capable of going as fast as you want.”

Calibration of the suspension worked okay for most of our testers. Balance between both ends was good too, but the fork and shock don’t offer the same level of comfort over bumps as the Honda and Yamaha. Still with most folks modifying their suspension to suit personal taste, that’s a small issue.

“It takes more energy to ride for sure,” says Milan. “And it brings up flaws in the suspension. The Kawi is another bike I would need stiffer springs to race, and part of that is because it has so much motor.”

When everything was on the line in Super Lap the Kawasaki shined at the controls of Simon with him setting his fastest time of the test (1’43.6). See also got along well with the Kawi lapping Zaca in a time of 1’47.8 (fourth-fastest).

Considering how much extra speed is generated due to its engine performance, a strong set of brakes is important. And that’s the one area that the Kawi came up short. With a faster rider at the controls power from the front brake didn’t seem as strong as the other bikes, but they delivered comparable levels of feel as the other Japanese bikes.

After the bikes were parked and gear bags loaded, the Kawasaki emerged the winner by a margin of just two points due in part to its engine package. Sure it’s not the sharpest handling bike, but it fits a wide range of riders. It’s also the bike that the majority of our testers chose if they were going racing.

Kawasaki KX450F Highs & Lows
  • Racing engine straight from factory!
  • Great adjustable ergonomics 
  • Adequate handling
  • Could be lighter
  • Sluggish steering
  • Low braking power

2012 Kawasaki KX450F Photos
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2012 Kawasaki KX450F Technical Specs
2012 Kawasaki KX450F  8399.
Engine: 449cc liquid-cooled Single, DOHC, 4-valve
Bore x Stroke: 96.0 x 62.1mm
Compression Ratio: 12.5:1
Fuel Delivery: Fuel-injection
Clutch: Wet multi-plate, cable actuation
Transmission: Five-speed
Final Drive Gearing: 13F/50R
Front Suspension: Kayaba AOS 48mm fork, 22-position compression and 20-position rebound damping adjustment; 12.4 in. travel
Rear Suspension: UNI-TRAK-equipped Kayaba gas charged shock, 22-position low-speed and step-less high-speed compression damping, 22-position rebound damping and adjustable spring preload; 12.4 in. travel
Front Brake: 250mm petal disc, dual-piston caliper
Rear Brake: 240mm petal disc, 1-piston caliper Handlebar: Renthal
Front Tire: Bridgestone M403 80/100-21
Rear Tire: Bridgestone M404 120/80-19
Curb Weight: 250 lbs.
Wheelbase: 58.3 in. Length: 85.8 in. Width: 32.3 in. Ground Clearance: 13.4 in.
Seat Height: 37.6 in.
Fuel Capacity: 1.64 gal.
MSRP: $8399
Color: Lime Green
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